Hangers for porcelain enamelling furnaces

ABSTRACT

A multi-piece hanger for porcelain enamelling furnaces which can be assembled from sections of relatively short length. Because of the ability to build up a burning tool of any desired size from short sections, shell molding may be used for hangers of even large sizes, thereby eliminating problems connected with green sand molding.

O United States Patent 11 1 1111 3,789,995 Annal Feb. 5, 1974 [54] HANGERS FOR PORCELAIN ENAIVIELLING 2,562,683 7/1951 Schneider 211/113 X FURNACES FOREIGN PATENTS OR APPLICATIONS Inventor: James Annal, Evergreen Park, 693,782 9/1964 Canada 211/118 I 111. 1,115,265 5/1968 Great Britain 204/297 W [73] Assignee: The Fahralloy Company, Harvey, 111.

I Primary Exammer-Ram0n S. Grltts Flledi y 19, 1972 Attorney, Agent, or Firm-Alexander, Speckman and 21 Appl. No.: 255,014 Staples 52 us. 01. 211/113 [57] ABSTRACT [51] Int. Cl. A471 5/08 A m i-pi e hanger for porcelain enamelling fur- [58] Field of Search. 211/113, 118, 119; 248/340, naces which can be assembled from sections of rela- 248/339, 304, 301, 215; 432/261, 253, 258; tively short length. Because of the ability to build up a 204/297 R, 297 W; 118/500, 502 burning too] of any desired size from short sections, shell molding may be used for hangers of even large [56] References Cited sizes, thereby eliminating problems connected with UNITED STATES PATENTS green Sand moldmg- 603,940 5/1898 Carkin 248/340 9 Claims, 9 Drawing Figures PATENIED FEB 5 I974 sum a or g HANGERS FOR PORCELAIN ENAMELLING FURNACES This invention relates generally to-burning tools, and specifically to cast hangers used to support parts to be treated under elevated temperature conditions, such as heat-resistant alloy hangers used in continuous porcelain furnaces.

Hangers of the type described above are currently formed as a single, unitary structure, and usually range in size from about 12 inches to 30 inches in length, though larger or smaller sizes have been used. As is well known in the art, suchhangers are supported from suitable support structure, such as a hanger bar, and are moved through furnaces which may be up to 70 to 80 feet in length, each hanger having tips, usually in multiples of two, from which parts to be porcelain enamelled are suspended.

Hangers generally used at the current time have certain drawbacks, however, among which are the following.

Production costs of the conventional hanger are rather high due to inefficient mold utilization. Thus, because the length of a conventional one-piece casting may be longer than one side, or even both sides, of a shell molding platen, only one or at most a few pieces may be formed per platen, due to inefficient, though unavoidable, space utilization within the platen.

The quality of conventional hangers may not be as high as desired, and the scrap rate may be too high. Since green sand molding must often be resorted to, the metal may not run well, and the tips, particularly, may not be completely formed. Since machining incompletely formed tips is frequently more expensive than pouring a new casting, the scrap'rate may be quite high.

Cracking of the casting can be a serious problem. Since a casting may shrink one-fourth inch per 12 inches of length during solidification in the mold, cracking can be a serious problem particularly in the larger sized castings.

Service life may be unduly short due to excessive incipient and invisible cracks. Incipient cracks may not be visible upon inspection, but can result in failure after two or three trips through a 70 or 80 foot heat treating furnace.

Distortion can become a serious problem in the eonventional hanger construction. Thus, due to the substantial length of the unitary construction, substantial distortion can occur between an extremely exposed portion and an extremely protective portion due to the substantial temperature gradient from portion to portion.

Replacement costs may be rather substantial, since the failure of one tip requires discard of the entire structure, even though the remaining tips are in good condition. This can be particularly serious in the more complex 4. and 6 point constructions.

The hanger manufacturer may be forced to use the green sand molding process, which is .inherently more expensive than the shell molding process due to the substantial length of the .part. This may substantially increase the production scrap rate of the-auser due to the presence of burned sand which, when it drops onte 'a part being porcelain enamel treated in a furnace, will cause rejection of the part.

Accordingly, a primary objectnof the invention is to provide a hanger which is less expensive to manufacture than the conventional structure, due to better space utilization in the molding platens, such better utilization resulting in a larger number of pieces per platen.

Another object is to provide a consistently high quality hanger with a relatively low scrap rate.

A further object is to provide a hanger construction in which the problem of cracking in the mold is substantially reduced or eliminated.

Another object is to provide a new type hanger having better service life due to a reduction of incipient and invisible cracks.

Yet a further object is to provide a hanger which distorts less in service than conventional hangers of equal tip capacity.

Yet a further object is to provide a burning tool in which only one or at most only half the tips need be replaced upon failure of a tip whereby replacement costs due to tip failure are lower than with conventional constructions.

Yet another object is to provide a burning tool which is adapted for shell molding almost without regard to tool length whereby the users production scrap rate may be lowered by virtue of elimination of burned sand rejections.

Other objects and advantages become apparent from a reading of the following description of the invention.

These and other objects are achieved by the present invention which includes a multi-part construction, at least two of said parts being of substantially similar configuration, whereby they are interchangeable at will, and quickly and easily engageable and disengageable.

The invention is illustrated more or less diagrammatically in the accompanying drawings wherein:

FIG. 1 is a side view of an assembled, overlapped, interlocked Z-piece lid type burning tool;

FIG. 2 is a side elevation of the left portion of the burning tool of FIG. 1 to an enlarged scale;

FIG. 3 is a top-plan view of FIG. 2;

FIG. 4 is a partial side view of a second embodiment of the invention;

FIG. 5 is an end view of the open channel type ridge connector usable in the embodiment of FIG. 4;

FIG. 6 is-an end view of .the closed channel type ridge connector usable in the embodiment of FIG. 4;-

FIG. 7 is a partial side view of a third embodiment of the invention;

FIG. 8 is an end view of the open channel type ridge connector utilized in the embodiment of FIG. 7; and

FIG. 9 is an end view of a closed channel type ridge connector usable in the embodiment of FIG. 7.

Like reference numerals will be used to refer to like parts throughout the following description of the figures.

FIG. 1 illustrates an assembled, overlapped, interlocked, two piece lid type hanger assembly or coat hanger as it is sometimes known in the trade. The assembly 10 consists of, in this instance, two hanger componentsindicatedgenerally at 11 and 12, the hanger components being secured one to the other to form a substantiallyrigid, yet easily engageable and disengageable assembly.

The hangercomponents 11 and 12 are identical one to .the other, :and'a-description of one will suffice for a description of both.

Referring now to FIGS. 2 and 3, hanger component 11 includes a shank section 13 which terminates at its outer end portion in a tip section 14. Means for securing hanger component 11' to a similar hanger component are illustrated at the other end portion. Specifically, the securing means includes, in this instance, a pair of projection structures indicated at 15 and 16, which, in this instance, project substantially perpendicularly to the plane of the shank section 13. A pair of recesses are formed at 17 and 18. From FIG. 2 it will be noted that projection structure 15 is substantially vertically aligned with recess 17, and projection structure 16 is substantially vertically aligned with recess 18. A keyhole shaped slot is indicated generally at 19, the slot being of a size sufficient to receive a hanger bar or other support structure from which the hanger assembly is to be suspended. Since the specific construction of the keyhole shaped slot is not critical to the invention, it will be understood that similar suspending means may be employed. A pivot center is indicated at 20, at the center of expanded portion 21 of the upper end of the keyhole shaped slot. It will be noted that the pivot center is located horizontally between projection 15 and recess 17 on the one hand, and projection 16 and recess 18 on the other hand.

A plurality of apertures are indicated at 22 through 26. Apertures 22 24 are available for supporting hanger members from shank section 13 if desired. Apertures 25 and 26 are provided to receive fastening means for securing locking a pair of hanger components one to the other.

In the assembled condition of FIG. I, it will be noted that the inner end portions of the pair of hanger components are placed in overlapped, abutting relationship one to the other in such fashion that a projection on one hanger component is in engagement with a recess on the abutting hanger component. Thus, for example, projection 15 of left hanger component 11 is received in bearing recess 18a of hanger component 12, and projection 16a of hanger component 12 engages recess 17 of hanger component 11. In like fashion, projection 15a of hanger component 12 engages recess 18 of hanger component 11, and projection 16 of hanger component 11 engages recess 17a of hanger component 12. It will be understood that only one projection and one recess need be provided on each hanger component, if so arranged as to preclude rotational movement of one hanger component with respect to another, but as a practical matter two projections and two recesses are provided on each hanger component for additional stability and preclusion of separation of the hanger components resulting from clockwise movement of the components with respect to one another around pivot center 20.

In the abutting, overlapped condition of FIG. 1, apertures 25, 26 of the two hanger components 11 and 12 overlie one another and may receive any suitable fastener, indicated at 27, 28 which precludes unintended separation of the hanger components in a direction perpendicular to the plane of the components.

Referring now to the embodiment of FIGS. 4 6, it

will be noted that the inner end portion 31 of hanger component 32 merely terminates in an abutment surface 33 and carries no projections or recesses similar to those of the embodiment of FIGS. 1 3.

Means for securing one hanger component 32' to an- 35. The securement means consists of a connector member which includes at least one side plate 36 and an upper edge flange 37 as illustrated best in FIG. 5. Alternatively, a second side plate 38 may be provided which results in a substantially U-shaped cross section as indicated in FIG. 6.

A pair of generally vertically oriented abutment members are indicated at 39, 40 formed integral with side plate 36. In the embodiment of FIG. 6 the abutment members 390 may be integral with both side plates 36 and 38. In any event, the outer surface of each abutment member, measured from the pivot axis 20, forms an abutment against which the end surface 33 or 33a of hanger components 32 and 34 respectively engage. The undersurface 41 of upper flange 37 forms a bearing surface against which the upper surface of hanger component 32 bears in the assembled condition of FIG. 4.

The connector is secured to hanger component 32 by means of a suitable fastener 42 which passes through aligned apertures 43 in side plate 36, and 44 in hanger component 32. It will be noted the fastener 42 prevents unintended separation of the hanger component with respect to the connector, and edge flange 37 and abutment member 39 preclude rotational movement of the hanger component with respect to the connector in any direction.

In the embodiment of FIGS. 7 8, a construction is illustrated in which 4 hanger components, 48, 49, 50, and 51, are secured to aconnector structure 52. Again, as illustrated in FIGS. 8 and 9, the connector structure 52 can be formed either open faced, as in FIG. 8, or as a U-shaped member as in FIG. 9.

In either event, the connector includes generally vertically oriented abutment members 53, 54, 55 and 56, and apertures 57 60, which are aligned with similar apertures in the tongue sections 61 64 of hangers 48 51. As best seen in FIG. 7, abutment members 53 and 54 are spaced apart a distance equal or slightly greater than the width of tongue section 63 of hanger component 50, so that movement of the hanger component 50 with respect to the connector 52 is precluded when a suitable fastener is passed through the aligned apertures in the hanger component and the connector.

Abutment member 53 is also received in a generally U-shaped recess 65 in tongue section 61 of hanger component 48, which thereby precludes separation or movement of hanger component 48 with respect to connector 52. If desired, additional generally horizontally disposed abutment members 67 and 68 may be provided to form a slide-way for the reception of tongues 61 and 62 of hanger components 48 and 49.

In the use and operation of the hanger assembly of the embodiment of FIGS. 1 3, a pair of similarly shaped hanger components 11 and 12 are secured one to the other by the interlocking of the projections on one hanger assembly with correspondingly positioned recesses on the other hanger component, and separation is precluded by the use of fasteners 27 and 28. In this condition the hanger assembly may be placed on a hanger bar of porcelain enamelling furnace. Thereafter the parts to be porcelain enamelled may be suspended from the tip sections 14, 14a of the hanger assembly. If desired, hooks or other support means may be secured to apertures 22 24 for the suspension of additional parts to be porcelain enamelled.

Preferably, the top edge of the shank section or arms of each hanger component may be formed with knife edges. This makes possible the lengthwise horizontal placement of long, thin panels as the hanger assembly with suspended stove bodies, refrigerator panels, signs or other parts pass through porcelain enamelling furnaces at temperatures of from about l,200 F to about 1,600 F.

in the event the tip section fails in service, it is only necessary to remove fasteners 27, 28, disengage the defective hanger component,'replace it with a new component, re-secure the fasteners and place the assembly back in operation.

Since the split component design permits the shell molding process to be used for even the longhorn type coat hanger, production rejects due to dropping of burned-in sand is substantially eliminated.

Further, since each hanger component is only a fraction of the entire length, distortion due to temperature gradients from extremely exposed to extremely protected zones is minimized, and finally, since the construction permits a hanger assembly to be built up from a number of smaller parts, the possibility of failure due to opening of invisible cracks is very materially reduced.

It will be understood that further modifications of the invention will occur to those skilled in the art from a reading of the foregoing exemplary description of the invention. Accordingly, the scope of the invention is intended to be'limited, not by the'foregoing exemplary description, but solely by the scope of the hereinafter appended claims.

I claim:

1. A hanger component, said. hanger component including a shank section,

a tip structure at one end portion of the shank section, said tip structure being constructed to support a workpiece, and

a base structure at the other end portion of the shank section,

said base structure having a projection formed integrally therewith and extending generally laterally outwardly therefrom which is disposed to make contact with a recess formed on a similar structure, 7

said base structure having a recess defining a projection receiving seat formed integrally therewith which isdisposed to make contact with a projection formed on a similar structure,

whereby a pair of similar hanger components can be assembled directly one to another, I

said base structure further including means for supporting said hanger from a support structure,

said projection and said recess being disposed, respectively, on opposite sides of the support means.

2. The hanger component of claim 1 further characterized in that said hanger component includes two projections, said projections being disposed, re-

spectively, on opposite sides of the support means, and

two recesses,

said recesses being disposed, respectively, on opposite sides of the support means.

3. The hanger component of claim 1 further characterized by and including fastening means for fastening said hanger component to a similar hanger component.

4. A hanger assembly, said hanger assembly including first and second similarly shaped hanger components,

each of said first and second hanger components having a shank section,

a tip structure at one end portion of the shank section, said tip structure being constructed to support a workpiece, and

a base structure at the other end portion of the shank section,

each of said base structures having projection means formed integrally therewith and extending generally laterally therefrom and disposed to make contact with recess means formed on the other base structure,

each of said base structures having recess means defining a projection means receiving seat, said recess means being formed integrally with said shank structure and disposed to make contact with projection means formed on said shank structure whereby said hanger components are assembled directly one to another,

each of said base structures further including means for supporting its hanger component from a support structure,

said projection means and said recess means on each shank structure being disposed, respectively, on opposite sides of the support means.

5. The hanger assembly of claim 4 further characterized in that each shank section of each hanger component includes two projections and two recesses.

6. The hanger assembly of claim 4 further including fastening means which fasten said hanger components together.

7. A hanger assembly, said hanger assembly including first and second similarly shaped hanger components, each of said first and second hanger components having a shank section which terminates, at its outer end portion, in a tip structure adapted to support for a workpiece, and

at its inner end portion, a means for securement to a connector structure,

a connector structure,

said connector structure having an inverted, generally U-shaped recess for suspending said connector structure from a horizontally axised support,

a pair of abutment members carried by the connector structure, one on each side of said inverted U- shaped recess,

said'securement means on eachhanger component including an abutment member making abutting contact with an associated abutment member on the connector structure, and

fastening means for fastening each hanger component to the connector structure when the abutment members on the hanger components and the connector structure are in abutting contact with one another whereby rotation of the hanger components and the connector structure relative to one another is precluded.

8'. The hanger assembly of claim 7 further characterized in that said connector structure has a generally inverted U- shaped cross-section disposed to receive the shank ture, said tip structure being constructed to support a workpiece, and

a base structure at the other end portion of the shank section, and

fastening means for securing each hanger component of said second set of hanger components to the connector structure by its base structure 

1. A hanger component, said hanger component including a shank section, a tip structure at one end portion of the shank section, said tip structure being constructed to support a workpiece, and a base structure at the other end portion of the shank sectiOn, said base structure having a projection formed integrally therewith and extending generally laterally outwardly therefrom which is disposed to make contact with a recess formed on a similar structure, said base structure having a recess defining a projection receiving seat formed integrally therewith which is disposed to make contact with a projection formed on a similar structure, whereby a pair of similar hanger components can be assembled directly one to another, said base structure further including means for supporting said hanger from a support structure, said projection and said recess being disposed, respectively, on opposite sides of the support means.
 2. The hanger component of claim 1 further characterized in that said hanger component includes two projections, said projections being disposed, respectively, on opposite sides of the support means, and two recesses, said recesses being disposed, respectively, on opposite sides of the support means.
 3. The hanger component of claim 1 further characterized by and including fastening means for fastening said hanger component to a similar hanger component.
 4. A hanger assembly, said hanger assembly including first and second similarly shaped hanger components, each of said first and second hanger components having a shank section, a tip structure at one end portion of the shank section, said tip structure being constructed to support a workpiece, and a base structure at the other end portion of the shank section, each of said base structures having projection means formed integrally therewith and extending generally laterally therefrom and disposed to make contact with recess means formed on the other base structure, each of said base structures having recess means defining a projection means receiving seat, said recess means being formed integrally with said shank structure and disposed to make contact with projection means formed on said shank structure whereby said hanger components are assembled directly one to another, each of said base structures further including means for supporting its hanger component from a support structure, said projection means and said recess means on each shank structure being disposed, respectively, on opposite sides of the support means.
 5. The hanger assembly of claim 4 further characterized in that each shank section of each hanger component includes two projections and two recesses.
 6. The hanger assembly of claim 4 further including fastening means which fasten said hanger components together.
 7. A hanger assembly, said hanger assembly including first and second similarly shaped hanger components, each of said first and second hanger components having a shank section which terminates, at its outer end portion, in a tip structure adapted to support for a workpiece, and at its inner end portion, a means for securement to a connector structure, a connector structure, said connector structure having an inverted, generally U-shaped recess for suspending said connector structure from a horizontally axised support, a pair of abutment members carried by the connector structure, one on each side of said inverted U-shaped recess, said securement means on each hanger component including an abutment member making abutting contact with an associated abutment member on the connector structure, and fastening means for fastening each hanger component to the connector structure when the abutment members on the hanger components and the connector structure are in abutting contact with one another whereby rotation of the hanger components and the connector structure relative to one another is precluded.
 8. The hanger assembly of claim 7 further characterized in that said connector structure has a generally inverted U-shaped cross-section disposed to receive the shank sections of the hanger components within said inverTed U-shaped cross-section.
 9. The hanger assembly of claim 7 further characterized by and including a second set of hanger components, each hanger component in said second set of hanger components having a shank section, a tip structure at one end portion of the shank structure, said tip structure being constructed to support a workpiece, and a base structure at the other end portion of the shank section, and fastening means for securing each hanger component of said second set of hanger components to the connector structure by its base structure. 